"If you look at Islam, for example, the Prophet Mohammad's hair was long. He was very handsome."

But the federation's statement has also won praise from players like Mojtaba Jabari. He is on Iran's national team, which will play in next year's World Cup.

"Whatever they do, the form of a football player must be good," Jabari says.

"I think that because we're coming up on the World Cup, it's better for players to improve their skills instead of think about their hairstyles."

Setting an example

The federation reasons that players should respect the country's Islamic values and set good examples for Iranian youth.

The way the players do their hair in my opinion, is no problem - But if they want to pluck their eyebrows, that's a problem

22-year-old fan Mohammad

"Every country has a certain definition of [good] behaviour, clothing, speaking, and so on," says lawmaker Iraj Nadimi, a member of Iran's Parliamentary Sports Committee, which oversees the Football Federation.

"Here, it's the same thing. I think most of our athletes know this.

"Freedom is not based on individual tastes. For example, if I want to walk down the street with no clothes on, this isn't freedom. And we don't accept that an athlete be like this.

"Our athletes are role models, and they use public goods, like our stadiums, so they should observe these points."

Spectators

Usually only men are allowed to watch the games at Iran's stadiums.

Some spectators hold back their long hair with bandanas. Many sport ponytails, earrings, and gold necklaces.

Twenty-year-old fan Mohammad says instead of following the styles of Iran's professional football players, he prefers to copy those of musicians like Eminem.

Players' style has spread to the terraces

"The way the players do their hair in my opinion, is no problem," he says. "But if they want to pluck their eyebrows, that's a problem."

And 27-year-old Mehdi says the ruling limits the freedom of football players.

"It's very bad," he says. "I think all people are free, and we shouldn't mix sports and politics. It's not good."

It's not clear how violators of the ruling might be punished.

Some Federation members say players will be fined and banned from playing, but the written statement itself says players' observance of the guidelines will be "supervised" and "encouraged".